Tcl

Find and Update an XML Attribute Value

See more XML Examples

Demonstrates how to find an element in XML with a specified attribute name and then update the attribute value. Tcl

load ./chilkat.dll

# Let's say you have 2 XML files with identical structures as shown directly below,
# and you wish to update the values in the 1st XML file with those in the 2nd XML file.

# <global>
#     <phrase id="2FADisabled" value="2factor authentication disabled"/>
#     <phrase id="2FAEnabled" value="2factor authentication enabled"/>
#     <phrase id="2FAResetFailed" value="Failed to disable two factor authentication"/>
# </global>

# <global>
#     <phrase id="2FAResetFailed" value="Failed to reset two factor authentication"/>
#     <phrase id="2FADisabled" value="2FA authentication disabled"/>
#     <phrase id="2FAEnabled" value="2FA authentication enabled"/>
# </global>

# First, initialize each of the Chilkat XML objects.
# These could be loaded from files, but we'll just create them manually for this example..

set xml1 [new_CkXml]

CkXml_put_Tag $xml1 "global"
CkXml_UpdateAttrAt $xml1 "phrase" 1 "id" "2FADisabled"
CkXml_UpdateAttrAt $xml1 "phrase" 1 "value" "2factor authentication disabled"
CkXml_UpdateAttrAt $xml1 "phrase[1]" 1 "id" "2FAEnabled"
CkXml_UpdateAttrAt $xml1 "phrase[1]" 1 "value" "2factor authentication enabled"
CkXml_UpdateAttrAt $xml1 "phrase[2]" 1 "id" "2FAResetFailed"
CkXml_UpdateAttrAt $xml1 "phrase[2]" 1 "value" "Failed to disable two factor authentication"

set xml2 [new_CkXml]

CkXml_put_Tag $xml2 "global"
CkXml_UpdateAttrAt $xml2 "phrase" 1 "id" "2FAResetFailed"
CkXml_UpdateAttrAt $xml2 "phrase" 1 "value" "Failed to reset two factor authentication"
CkXml_UpdateAttrAt $xml2 "phrase[1]" 1 "id" "2FADisabled"
CkXml_UpdateAttrAt $xml2 "phrase[1]" 1 "value" "2FA authentication disabled"
CkXml_UpdateAttrAt $xml2 "phrase[2]" 1 "id" "2FAEnabled"
CkXml_UpdateAttrAt $xml2 "phrase[2]" 1 "value" "2FA authentication enabled"

# Iterate over attribute values in xml2 and update the same in xml1.

set sbPath [new_CkStringBuilder]

set i 0
set count_i [CkXml_NumChildrenHavingTag $xml2 "phrase"]
while {$i < $count_i} {
    CkXml_put_I $xml2 $i
    set phrase_id [CkXml_chilkatPath $xml2 "phrase[i]|(id)"]
    set phrase_value [CkXml_chilkatPath $xml2 "phrase[i]|(value)"]

    # Notice how the UpdateAttrAt method's 1st argument is a Chilkat path -- which is an expression
    # to find the location of the XML element to be updated.
    # Here we create a path of the form "/A/tagName,attributeName,attributeValuePattern", which means
    # find the direct descendent of xml2 having tag=tagName, with an attribute=attributeName where the attribute value
    # matches the attributeValuePattern.  If attributeValuePattern does not contain a "*", then it must match directly.
    # We'll build a Chilkat path such as "/A/phrase,id,2FADisabled"
    CkStringBuilder_SetString $sbPath "/A/phrase,id,"
    CkStringBuilder_Append $sbPath $phrase_id

    # This assumes the corresponding element exists in xml1.
    CkXml_UpdateAttrAt $xml1 [CkStringBuilder_getAsString $sbPath] 1 "value" $phrase_value

    set i [expr $i + 1]
}

# Now see how xml1 has been updated..
puts [CkXml_getXml $xml1]

# <global>
#     <phrase id="2FADisabled" value="2FA authentication disabled"/>
#     <phrase id="2FAEnabled" value="2FA authentication enabled"/>
#     <phrase id="2FAResetFailed" value="Failed to reset two factor authentication"/>
# </global>

delete_CkXml $xml1
delete_CkXml $xml2
delete_CkStringBuilder $sbPath